The invention relates to a tamper-evident container assembly and, more particularly, to such a tamper-evident container in which the closure is internally threaded, the threads of which are formed prior to the cap being placed on the dispensing end of the container.
Goods such as food, medicants and cosmetics are potentially dangerous to consumers if they have been contaminated before reaching the consumer. It is often difficult to determine by looking at the goods themselves whether the container has been opened prior to reaching the consumer because many goods themselves do not given an observable indication, such as a color change or odor, if they have been contaminated.
Thus, many producers of such goods package their goods in such a way that a consumer can readily examine a container and tell whether the contents of the container may have been tampered with after the container was packaged. Such packaging often involves a seal or other indicia, either associated with the cap or the container, that is broken or otherwise altered when the container is initially opened so that the seal or indicia can not be replaced or repaired in the same condition. Thus, when such a seal or indicia is in a condition different from its initial condition, the contents of the container should not be used because they could have been contaminated.
Various types of tamper-evident seals are available in the art. An advantageous feature of some of such seals is that the cap, or other sealing means, be reusable after initially being separated from the container, even in its altered condition.
U.S. Pat. Nos. 1,968,747, 2,045,388 and 3,165,220 disclose tamper-evident containers in which a tab extends outwardly from the threaded neck of the containers. The tabs must be separated from the containers before the closures can be removed to open the containers. Thus, the lack of a tab on the containers indicates that the containers have previously been opened. U.S. Pat. Nos. 1,968,747 and 2,045,388 require that the tabs be separated from the containers in a separate step. The tab in U.S. Pat. No. 3,165,220 can be separated from the container by twisting the closure with respect to the container as the closure is initially removed from the container. The closure are readily used to reseal the containers.
The closure of U.S. Pat. No. 3,165,220 includes lugs on its inner surface that correspond to the threads on the neck of the container and a notch corresponding to the tab or button. In order to initially secure the closure to the container, the closure is positioned on the container and axial pressure is exerted over the closure toward the container. The closure is slightly deformable to enable the lugs to pass over the threads of the container and snap back into place.
In order to form a tight seal with a container having a threaded neck, it is often desired to have a closure that includes an internally threaded surface, the threads of which are complementary to the threads of the neck of the container. A concern associated with the use of internally threaded closures on containers with a break-away tab is the initial placement of the closure on the container without disturbing the tab. The internal threads of the closure of U.S. Pat. No. 2,045,388 are formed as the closure is placed over the neck of the container. The closure of U.S. Pat. No. 1,986,747 requires inner and outer cap members, neither of which interferes with the tab as it is placed on the container. The threaded inner cap member is required to form a tight seal and is not large enough to reach the tab. The outer cap member is not threaded and is placed over the inner cap member and cemented thereto to form a unitary closure. These closures are cumbersome and the process of placing them on the container involves several steps and is unduly complex.
Thus, it is desired to develop a tamperevident container in which the closure is internally threaded, the threads of which are formed prior to the cap being placed on the dispensing end of the container.